Yammy Llargo

Yammy Llargo is one of the most physically imposing characters in Bleach. He is the 10th (and therefore lowest-ranked) Espada in Aizen's army, but he also has the potential to become the 0th Espada due to his unique power.

Key points about him:

• Appearance: Extremely large and heavily muscled, one of the biggest characters in the series. He has a very brutish, ogre-like look with dark skin, orange hair, and a rather simple-minded personality.
• Personality: Arrogant, hot-tempered, violent, and not particularly intelligent. He frequently gets angry very quickly and looks down on others (especially humans and weaker Arrancar).
• Ability: His power is tied to his rage — the angrier he becomes, the larger and stronger he grows. In his Resurrección (named Ira — "wrath" in Spanish), he transforms into an enormous, Hulk-like monster whose size and spiritual power increase dramatically the more damage he takes and the more furious he gets.
• Nickname: Often called "the idiot" or "the raging brute" by other characters (and even some fans).

In short: Yammy is the "strength through sheer size and anger" type of villain — a classic powerhouse with very little subtlety or tactical thinking.

(And yes, he's famously the Espada whose number flips from 10 → 0 when he releases, making him temporarily the strongest Espada by raw power in that form.)